If you want to talk about events, I'm going to compare them with 2 other mobile games I play, 7K and Granblue Fantasy. (Discussion thread, I'm discussing, not advertising)
7K - Most events up to this point does not differentiate between new or old players. As long as you do X number of runs in Adventure, Arena, Tower or Raids. As long as you do those many runs in a day, you can complete it easily.
Granblue Fantasy - Nickname "Grindblue Fantasy" because of the grinds required to finish the event. Every event is RNG and gacha based to the point where is fair. If you want more weapons, grind more.
Note the keyword is "fair". This event just gives a huge wall for players to jump over. I also understand that it's a matter of game mechanics. This just says that "Don't have this hero? Too bad lol spend more money!"
Even tough i like those suggestions i did not like the use of the words "complete easily". The previous event whas just that ( a part from the arena achievement ), grinding for days on auto. No strat, no gameplan , launching the fight and not even looking at the phone. It was boring as hell.
This event offeres a real challenge in legendary. It pushes us to the limits of our skills and knowledge. If the event becomes as you state easy...how long will it last until people get bored of it?
Some will achieve 100% and others dont.
I find this game fabulous, well balanced out and a delight to play, i would hate it if the game becomes over simplified and too easy to a point of boredom.
Most mobile games have a short life span because they get boring to fast. Lets not apply the same thing here.
Everyone will eventually be at the same level, but to do so they have to take every step of the game and not force the devs to lower the standards of the game.
Sorry for the long rant.
Granblue fantasy has bosses that are easy to "one shot you" difficulty depending on whatever your weapon or character pool is. The rewards are the same, just how much you have to grind to get them. Certain bosses require certain strategies like buff removals, damage reflect and whatnot.
A challenge is something that is not easy yet obtainable by the general player base regardless of level. Granblue has an event just 2 months ago during the idolmaster collab event. It offers a hidden Rank Kanzaki SR character that has a ridiculous requirement thats challenging but not impossible.
An impossible task is setting ridiculous requirement walls like the 21 stars requirement that at least half of the player base will not be able to do, on the 3rd week of release. I went in and my Cybella died on turn 3. She has a 4* set with +15 equips and she still died so quickly.
I agree that the game should not be too easy, it gets too boring, neither should it be impossible. I admit that 7K got boring after a while. I've also played Tower of Saviors (1k day player) and basically given up because the game is too hard. I spent 70 diamonds just to get Giemsa when she was first released which is like 70 dollars+. So what, i should spend 500 gems to finish the event, just for 100% completion and better loot? If so, i would just uninstall now and not waste my time. There are better events with stories and a challenging boss fight that are more thought of thoroughly than a wall.
The gameplay is decent and engaging, if you want to turn new players away from playing, this is how you do it, with a goddamn wall, on the 3rd week.